Knife sharpener

[Kyle Kraft]

Do any of you folks know of a good, relatively foolproof:) gadget to sharpen kitchen knives? I can obtain a pretty mean edge on my chisels using the Veritas MK II but I suck at the freehand stuff. I've tried a steel and ceramic rods, etc. and all I do is polish the dull edge.

Any/all ideas will be helpful.

[Lewis Moon]

Actually, I use a variant of the Scary Sharp sandpaper method on a 4 X 8 granite tile. Use 220-320 to re-establish the edge then move up through the grits to about 2500. Cut out a piece of sturdy card board at around 15 degrees to use as a reference for where to hold the blade.

[Jason Roehl]

There are various gadgets out there that have you draw the knife through a series of v-shaped carbide and diamoned-embedded steels. They're okay, but I find that while they are quick, they don't do well at the tip of the blade. My favorite, but more time-consuming, is a T-jig that clamps to the blade, then you have a series of stones with guide bars on them that pass through a slot on the jig. There are several slots for various sharpening angles. Like this:

http://www.actiongear.com/cgi-bin/tame.exe/agcatalog/results.tam?mailcall=ppjsg&query.ctx=gatco%20sharpeners&gclid=CP7Ev5nL048CFTyKOAod80Ri9Q

[Scott Brihn]

I achieve a keen edge of consistent shape using a Viel S5 Sander/Grinder with a 42", 15 micron silicon carbide belt and follow that with some chromium oxide on leather.

Prior to the Viel I used a 1000g waterstone.

Both methods are freehand but controllable.

[Tim Put]

Freehand scary sharp. It's really not too hard. Just move up through grits without skipping, all the way to 0.5 micron.

I hold the blade with my fingers on the spine of the blade as an angle stop, moving up a degree or two every grit (sacrilege I know, but it works). My pocket knife's edge looks like a mirror even under 60x magnification, it can cut a hair in two from the side.

[Carl Eyman]

were both prety good using a "steel" . By that I mean a steel rod fitted with a wooden handle which was actually a file. All the "teeth" of the file were vertical flutes. Butchers used them all the time. For the first 60 years my wife and I were married I used the same thing. Had varying results. Finally the thing wore out. I tried the same techniques I used in the shop with mixed, mostly poor, results. A few months ago found a new "steel" in Walmart . It has imbedded diamonds. Works like a charm. A couple of passes of the carving knife over this synthetic steel, and I'm a better carver that chef Paul Prudhomme.

[Mike Henderson]

I agree with Carl that a good "steel" is a necessity for knives. No matter how sharp you get them on a stone or scary sharp they dull fast in use. It is only by using a steel that you can get the edge back to a usable sharp edge quickly (when when you're using the knife).

Carl, I'm going to look for one of those diamond "steel" things. I've used real steel for a long time but they all wear out.

Mike

PS - If you want a replacement steel, LV sells them without a handle for a low price. It's easy to turn your own handle if you have a lathe.

[Tom Maple]

I've had success using a diamond "steel" made by Henckel, the German cutlery maker. It has a rougher side for when a knife is pretty dull and a finer side for the finished edge. They should be available at any good cutlery store.
If a knife is extremely dull or damaged, or needs to have the bevel reestablished, a series of stones or sandpaper would need to be used first. A bevel gauge would be helpful for that chore. Good luck.

[Kyle Kraft]

Thanks for the great ideas!! The granite plate has been on my wish list for some time, the Gatco honing guide looks like it's relatively foolproof, and theres a Wally World a few miles away.....Thanks!!!!

[BEN SHELTON]

My experience with "steels" is a little bit different. The first ones I ran into were not toothed nor did they have any grit. They were smooth, hard steel and I never knew how they worked. Dad had worked as a butcher he didn't know how they worked either, they just worked. Stroke the knife along them an even number of passes on each side (right, left right left is easiest)

Then I ran across a cabinet scraper and read up on sharpening scrapers. In my experience the steel is a burnisher that is used to realign the folding edge the same way a scraper burnisher is used to roll the scrapers edge over. The only difference with a scraper is that the edge geometry is different. For a knife, the edge is a more acute angle and is therefore much thinner. The steel, when used equally on both sides of well honed edge, pushes up a burr right in the middle of the edge instead of rolling it over to one side as on a scraper.

That is my experience. I really don't think that any tool that has an abrasive or cutting action is really a steel. I'd call it a hone but since the manufacturers can't be swayed by such semantic arguments I suppose the misnomer "steel" will stick, just as "native American" is used to refer to American Aboriginals. That's all just semantics and people hardly ever get those right. Growing up in Texas we used the word "coke" to refer to any brand of carbonated beverage. I only realized how incorrect that was after I moved away.

Regardless of whether you want to use a stick hone or steel for edge maintenance, you will have to properly shape the edge first. The previously mentioned methods are all great and outline the guiding principal. Maintain the correct angle as you proceed through increasingly finer grits. Finish with a steel or a strop to deal with the burr.

Of course the strop is a whole different ball of wax(with embedded grits)

If you are in the market for sharpening stones I can highly reccomend the Smiths brand diamond stones. I got a 700 grit 6" x 2" stone from one of the huge online sporting goods places for a reasonable price and it is the fastest cutting thing I have used. I can't even imagine what the 320 grit version is like. If you're looking for an oil stone look into the Norton combination india stone. The orange fine grit side is awesome for establishing bevels and produces a fairly fine edge. Fine hard arkansas to follow and you can't go wrong.

Have fun
A sharp knife is a treat to work with.

Ben

my 2 cents worth

[John Borgwardt]

I bought a granite or marble floor tile 12" x 12". It seems to be flat and it works great for the scary sharp system. If I remember I paid around $ 8.00 for it. My $.02 :rolleyes:

[Alex Yeilding]

Check your sharpening angle. I may be stating the obvious to you, but it was an "aha" for me when I realized that a relatively low sharpening angle for a chisel or plane iron, such as 25 degrees, gets doubled for a knife blade when you are sharpening from both sides. So to get a 25 to 30 degree angle, the blade of the knife has to be nearly lying flat on the stone, or at least it feels that way compared to sharpening single-bevel tools.

Doing a little trig, the back edge of the knife should be about 1/4 of the blade width above the stone (to get a 30-degree cutting edge). So for a 1/2" wide blade, the back is only 1/8" above the stone. I have to be very concious of this because it "feels" more right to go to a 25 to 30 degree angle I am more familiar with.

[Bruce Haugen]

I'm with Tom,
My brother, a professional chef, gave us a Wusthof diamond steel, and my kitchen knife sharpening concerns were over as of that day. They don't burnish like a regular steel does, they actually sharpen. Quickly, too.

Bruce

[lawrence rottersman]

You can sharpen a knife on almost anything, like a stone window sill in a pinch. But kitchen knives, with all respect to my fellow woodworkers, is a question best asked to cooks. I suggest the EdgePro

www.edgeproinc.com

The Edgepro will actually do scissors and plane blades and hunting knives, but it is really, I think, dedicated to sharpening kitchen knivesj, and it does them fast, accurately, with a lot of lattitude: chopping, slicing, etc.

Need I say, which I say anyway, no affilitation except as a customer. Hope this helps, and don't nobody be offended, please ;)

[BEN SHELTON]

Here's my method.
The only "extra" tools it requires is a $20 dial caliper.
If the knife has no flat, parallel faces like those on a folding knife you will have to determine your angles based on the width and thickness of the blade.
Find the average thickness of the spine of the knife and the average width of the blade. I usually use the thickest, widest part of the knife.
Decide on a sharpening angle (I use 25 deg for pocket knives and 20 for kitchen knives)

Now comes the math. Divide your chosen edge angle in half. Divide the thickness of the spine of the knife in half. You want to hold the centerline of your knife at this angle to the sharpening surface. We now need to know how high of the surface to hold the spine of the knife. Given the width of the blade and the angle we can use trigonometry to find the height or we can use the rise and run.

For a 20 degree edge the angle rises 0.1763" per inch.
For a 25 degree edge the angle rises 0.2217" per inch.

I can't measure to the 0.0001" so I use 0.176" and 0.222"

So lets do an example

take a knife with a 5/8" wide blade, 0.093" thick, sharpened to a 25 deg bevel.
The important numbers are
12 1/2 deg sharpening angle (0.222" rise per 1" run)
0.0465" (half the blade thickness)

(rise per inch x blade width) - half the blade thickness
(0.222 x 0.625) - 0.0465 = 0.092

set your calipers to 0.092" and use the inside measureing side to keep the spine of the blade at that height for the beginning of each stroke.

You can also use a #10-32tpi screw to set this height too. For each full turn the 32 tpi screw will raise or lower 1/32" 0.03125". In our example we need to raise the spine of the blade 0.092 off the parallel with the sharpening surface.

0.092/0.03125 = 2.944 turns

if you use a flat headed screw and set it flush with the stone then turn it 3 times you'll be right on track. You may want to use two nuts as your height gauge so that you can lock them in place.


Now,
this is how the poor boy with more time than money does it. On the other hand, I LOVE the sharpening jig mentioned in the above post. I don't have one but Man what a cool tool.

Ben


Have fun

[lawrence rottersman]

Ben, your post was easily the most creative I have ever seen on sharpening knives, and also the most diet-effective :) Larry